This 34-year-old is on the fast track to reach a $1 million net worth: '7 money habits to adopt before you turn 40'

At 34, Mandi Woodruff-Santos has a net worth of $700,000 — mostly from her income, retirement savings, home equity and investing accounts. Now, she's on track to reach a $1 million net worth by age 40. Here are her top money habits.